Biochemical Test of Bacteria

Milk is an excellent medium for the growth of microorganisms because it contains the milk protein casein, the sugar lactose, vitamins, minerals and water. Litmus milk is a milk-based medium used to distinguish between different species of bacteria. The lactose (milk sugar), litmus (pH indicator), and casein (milk protein) contained within the medium can all be metabolized by different types of bacteria. The test …